Time series data is essential in the environmental sciences, both for research and for timely monitoring and warning of increasing climate extremes. The seven Helmholtz Centers in the research field Earth and Environment (E&E) operate some of the world's largest environmental measurement infrastructures. Despite previous efforts, a unified, community-driven framework for time series and sensor metadata is still lacking. The STAMPLATE project fills this gap by developing technical and semantic foundations to establish the SensorThings API as a flexible, interoperable standard for publishing time series data with standardized metadata. All seven centers are involved, supported by Fraunhofer IOSB and the Open Geospatial Consortium.